Building an east-west high speed rail link connecting cities across northern England would bring considerable economic benefits, said Chancellor George Osborne.
Representing a further step in the controversial HS2 project, the HS3 could connect the two proposed branches of the second phase of HS2 – one leading from Birmingham to Manchester and the other one to Leeds.
Speaking at Manchester's Museum of Science and Technology, Osborne said the cities of the English North including Manchester, Leeds, Liverpool, Sheffield and Hull, with an overall population of 10 million, have the potential to become a second economic power house of the UK, successfully competing with London.
However, he said, the major obstacle to realise this potential is the poor transportation links between the cities. Getting from London to Paris by train is actually faster than crossing half the distance between Liverpool and Hull, and it is quicker to drive from Southampton to Oxford than to cover a journey half as long between Manchester and Sheffield.
To help unleash the economic potential of the North, Osborne promised to propose the HS3 link as part of the review of the second phase of the HS2.
"We need an ambitious plan to make the cities and towns here in this northern belt radically more connected from east to west - to create the equivalent of travelling around a single global city," said Osborne.
Speaking to BBC1’s Breakfast, he said the project could come in at around £6-7bn if priced at the same cost per mile as HS2, but was likely to work out cheaper because it would be able to use existing rail corridors.
“There is great potential through the connections to the east and west coast main lines for cities other than Birmingham, Manchester and Leeds to benefit from HS2, but the challenges around realising these benefits need to be tackled now if these locations are not to fall behind,” Jeremy Acklam from Institution of Engineering and Technology commented on the announcement.
“We need to think long and hard about the cities we include in the proposed HS3 linking Manchester and Leeds. Examples could include Liverpool via Warrington and Preston via Bolton in the west, which will also allow high speed services to run from London to Liverpool and London to Preston. In addition, from Leeds, the line could be extended to Darlington and Newcastle via York.
“To increase the project benefit to the north, further assistance will be needed to ensure that northern cities are well prepared for bringing forward infrastructure work. In particular planning to fast-track the development of employment and local transport infrastructure will be required.
However, some experts have warned the difficult terrain such an east-west link would have to cross may represent a major challenge.
"There's no question the Osborne plan is feasible. It's by no means impractical," said Jim Steer, a former managing director of strategic planning at the Strategic Rail Authority and director of high-speed rail research company Greengauge 21.
“The Swiss are building tunnels through the Alps so it should be possible to build them through the Pennines. Clearly, the route will have to be chosen carefully. But there is certainly a need for better cross-Pennine transport links.”
Currently, rail journey times across the Pennines are extremely slow, with speeds averaging around 40mph.
The fastest rail services between Leeds and Manchester currently take about 50 minutes but the plan would cut this to 30 minutes, with trains travelling at up to 140mph, compared with the current maximum of 90mph.
"A new route would provide so many options. You could run high-speed Channel Tunnel Eurostar trains along the route as well as freight. It would be a big boost for the north of England,” Steer said.
But Richard Wellings, deputy editorial director and head of transport at the Institute of Economic Affairs, was far from impressed with the Osborne plan.
He said: "The relatively short distances between northern cities mean that high-speed rail is an expensive and inefficient way of linking them together.
"The Chancellor should be focusing on smaller-scale schemes that deliver high returns for the taxpayer or, better still, that can be financed privately, rather than concocting a headline-grabbing vanity project designed to attract votes."